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In my last two posts I commented on an essay by Benito Feijoo. First we examined how he pictures the history of philosophy as the contest between two ladies —Solidína (experience) and Idearia (imagination) — to conquer the world. He sides with experience, and we also examined some of the arguments he gives to support the adoption of the experimental method and the rejection of mere speculation. In today’s post I want to follow Feijoo further, examining in particular his thought that just as we must abandon speculation when it is unaided by experience, we must also be cautious and keep in mind that experience without reasoning can also lead us astray in our quest for knowledge.

After spending most of his essay showing (through examples) that the proper path to knowledge is to follow the experimental method, Feijoo concludes with 3 capital errors that frequently take place in our experimental observations:

We shall conclude this discourse, by pointing out three capital errors, which stem from lack of reflection in experimental observations. The first is that of taking for the effect that which is cause, and for cause that which is effect. The second is to take for cause something that only happens accidentally and has no influence at all. The third is, between two effects of the same cause, to take one as the cause of the other. I shall show examples of these three errors in observations pertaining to Medicine.

Of the first type of mistake Feijoo gives us a case where someone drinks water excessively to quench an overwhelming thirst. A few hours later such person suffers a fever, and it is commonly thought that the cause of the fever is the excessive consumption of water. However this is a false conclusion due to the lack of reflection when observing. If we reason, we can see that the sickness is the cause of the thirst that leads to the excessive consumption of water.

Feijoo warns us that this kind of mistake is very dangerous in medicine, since the lack of reflection and reasoning leads the physician to err in his diagnosis and prevent him from curing the disease.

The second kind of mistake takes place when we assign as the cause something that only happens accidentally. Feijoo tells us that this mistake is committed frequently by ‘superstitious souls’ that constantly assign to their diseases causes that have nothing to do with it. The most common mistaken cause in these cases is the weather. Patients frequently blame their disease on the weather: If during summer the weather is hot, the disease is taken to be caused by the excessive heat, but if summer is not hot enough, then this is also taken to be the cause of the disease.

Finally, the third kind of mistake happens when between two effects of the same cause we take one to be the cause of the other. Feijoo’s example is that of a man that performs an intense physical exercise or activity, then drinks alcohol in excess, and later suffers a fever. While most men would take the excessive drinking to be the cause of the fever, the truth is that intense exercise is more likely to cause a fever than excessive drinking.

This account of capital errors in experimental observation concludes Feijoo’s essay. So what are we to make of his thoughts on the ‘Lessons of Experience’? Well I believe that in Feijoo we have a clear example of the dispersion of the experimental method across the Iberian Peninsula in the first half of the eighteenth century. Feijoo might be the most influential figure of this period in Spain, but he certainly was not alone in the adoption and promotion of the experimental method: Andres Piquer, Manuel Martinez, Juan de Cabriada, and the circles of doctors in Seville and Valencia all shared the beliefs Feijoo expresses in his text. As we have seen in Feijoo’s work, the novatores believed that the correct path towards knowledge was the one taken by Bacon, Boyle, and Newton.

As we have already noted on this blog, “empiricism” was mainly used as a medical term in the early modern period. It referred to empirical physicians, a movement that had its origins in ancient Greece. Greek empirical physicians claimed that our knowledge of medical cures derives entirely from experience and derives its justification from experience. It does not derive from any insight into “hidden natures, causes, and actions, not open to observation, but only accessible to reason, e.g., atoms, invisible pores, functions of organs, or essences” (Michael Frede).

These views of ancient empirical physicians were remarkably close to those of the early modern physicians who were associated with the experimental philosophy. They too rejected reasonings from principles and speculations on hidden essences and claimed to derive their cures from experience alone. The early moderns were conscious of this similarity between ancient empirical physicians and modern experimental physicians. They acknowledged that, since empirical physicians relied on “experiments” (that is, experience), their teachings contain “something that is certaine & experimentall” (Hartlib Papers).

In the light of this, it is puzzling that the upholders of the “experimentall” approach to medicine used to criticize medical empiricism and empirical physicians. They generally accepted the then common association of empirical physicians with “Mountebanks, pretended Chymists, Apothecaries, Chirurgeons, Midwives, &c. in which piece of Folly the English surpass all the Nations of Christendom.”

To be sure, there were some cases in which early modern experimental physicians praised ancient medical empiricism, portraying it as a forerunner of experimental medicine. But as far as I know, these were rare exceptions. Why were they exceptions and not the rule? Why did experimental physicians see themselves as opponents, rather than followers, of medical empiricism?

I have found some answers to these questions in the writings of two prominent eighteenth-century physicians. They are the German physician Friedrich Hoffman, a leading systematist of the early eighteenth-century, and the Scottish physician John Gregory, who taught at Edinburgh in the latter half of the century. They both associate medical empiricism with the application of medicines that happened to work in past cases to patients which display similar symptoms. This approach was epitomized in the “empirical books” that were compilations of medical recipes and cures for all sorts of diseases. According to Gregory, this approach raises two problems.

Firstly, it relies on experience in the wrong way. Empirical physicians rely on the recipes that have been shown to work by experience, but true physicians should also rely on experience to improve their remedies and practice.

Secondly and more interestingly, empirical physicians did not pay sufficient attention to experience. They did not carefully inquire into the circumstances of individual patients. Instead, having noted few symptoms, they hastily prescribed a familiar remedy. As Hoffmann pointed out, this “obtuse and most dangerous empiria” was deeply flawed because the “efficacy of a cure” does not reside in the nature of a remedy, but in the way in which the remedy interacts with the specific circumstances of a patient. In Gregory’s words, since “empirics” paid insufficient attention to those circumstances, “notwithstanding their pretensions of relying upon experience alone, have in truth abandoned it”.

Gregory’s preferred alternative to this flawed medical empiricism was what appears to be, broadly speaking, an application of the Newtonian experimental method to medicine. Gregory praised a medical theory that “is produced by practice, is founded on facts alone, and constantly appeals to them for its truth”. He rejected the use of hypotheses, considered as principles devoid of “proof from experience”. He advocated their use, as long as they were “proposed in the modest and diffident manner that becomes mere suppositions or conjectures”, that is, queries. Used in this way, hypotheses “are not only harmless but even necessary in establishing a just theory in medicine”. Gregory portrayed this experimental method as an alternative to medical empiricism. Only one century later, after “empiricism” took on a new meaning, did it come to be regarded as a positive stance even within medicine.

Center for the Philosophy of Science, University of Pittsburgh
2-4 November 2012

The aim of the conference is to bring to the fore the medical context of the ‘Scientific Revolution’ and to explore the complex connections between medicine and natural philosophy in Renaissance and Early Modern Europe. Medicine and natural philosophy interacted on many levels, from the practical imperative to restore and maintain the health of human bodies to theoretical issues on the nature of living matter and the powers of the soul to methodological concerns about the appropriate way to gain knowledge of natural things. And issues of life, generation, ageing, medicine, and vital activity were important topics of investigation for canonical actors of the Scientific Revolution, from Boyle, Hooke and Locke to Descartes and Leibniz. Recent efforts to recover the medical content and contexts of their projects have already begun to reshape our understanding of these key natural philosophers. Putting medical interests in the foreground also reveals connections with a wide variety of less canonical but historically important scientists, physicians, and philosophers, such as Petrus Severinus, Fabricius ab Aquapendente, Lodovico Settala, William Harvey, Richard Lower, Thomas Willis, Louis de la Forge, and Georg Ernst Stahl. This interdisciplinary conference will bring together scholars of Renaissance and Early Modern science, medicine and philosophy to examine the projects of more and less canonical figures and trace perhaps unexpected interactions between medicine and other approaches to studying and understanding the natural world.

Submission of extended abstracts for individual paper presentations (limit 30 minutes) are invited. More information is available here.

It is often supposed that the term ‘empiricism’ in its Kantian sense would have been entirely foreign to philosophers of the early modern period. For, throughout the seventeenth century the term ‘empiric’ had pejorative connotations. When used in medical contexts it normally referred to quacks: medical practitioners who are untutored, but who have pretentions to therapeutic medicine on the basis of experience alone. By extension, the term came to mean imposter or charlatan.

Yet when used as a name in the plural, ‘empirici’, it often referred to those ancient physicians who relied on observation over theory in their therapeutic medicine. Needless to say, those physicians in the early modern period who were associated with the experimental philosophy affirmed this emphasis on observation. It is worth inquiring, therefore, as to whether the term ‘empiric’ was ever used in a positive sense and whether physicians were proud to be labeled empirics?

One early use of the term ‘Empericism’ is in the chymical physician George Starkey’s Nature’s Explication (1657). But Starkey uses the term pejoratively in criticizing the Galenists who relied too heavily on theory. He says:

the Chymistry of the Galenical Tribe is a ridiculous pardy [sic.], and partly dangerous Empericism, in stead of so commendable a Method and Art, as they with confidence and impudence sufficient boast it to be (p. 245)

Here Starkey is inverting the charge normally laid at the feet of the chymical physicians, namely that they were untutored quacks. Starkey implies that the Galenists were untutored in the chymical arts.

Interestingly, however, just over a decade later, the chymical physician George Thomson, when defending the chymical physicians against the charge of being empirics (made by Henry Stubbe), picks up the positive connotation of ‘empirici’ and aligns the chymical physicians, including himself, with empirics in so far as they are the true experimental physicians. In his Misochemias Elenchosor, A Check given to the insolent Garrulity of Henry Stubbe … With an Assertion of Experimental Philosophy (London, 1671), Thomson says the following:

We shall examine the Original derivation of the word Empiricik, which arises frompeirazo velpeiraoexperior, vel exploro, to try, assay, or prove, to review or find out any thing by diligent searching: so then empericos is but an Experimental Physician, one of a Sect very well allowed of by the Ancients: … who as Celsus delivers hath acquired the knowledge of Physick only by Use and Experiments, so he treats of it, not able to give a Natural Cause thereof. … I wish ye would be so Ingenious as your Tutor, to confess the greatest knowledge ye have obtained in the Iatrical part of late, hath been delivered to you by such Empiricks as ye abusively nominate me (p. 5).

Thomson goes on to liken the chymical physicians to ‘the poor Experimental Chymical Samaritane, carrying some Balsamical Remedy about him, poureth it in with his own fingers, taking care of the Patient to purpose. Such an one I profess my self, but yet not an Empyrick according to H[enry] St[ubbe]’ (p. 6).

Here in a book defending experimental philosophy, just as we find 100 years later in a book from 1771 by the German physician Georg Zimmermann, the term ‘empiric’ is explicitly aligned with the experimental philosophy as applied in physic, that is, therapeutic medicine. This, in turn, is suggestive of the origins of the positive association of ‘empiricism’ with an emphasis on observation. It may also reveal something of the origins of Kant’s use of the terms ‘Empirismus’ and ‘Empiristen’ to refer to those who emphasize the acquisition of knowledge by observation and experiment.

Following Peter Anstey’s post on 17th-century experimental medicine I want to continue shedding light on the topic, but I will be focusing on 18th-century experimental medicine. In particular, I want to examine the Monro dynasty and the role they played in the instruction of medicine in Edinburgh for more than a hundred years.

From 1726 until 1846 the chair of anatomy at the University of Edinburgh was held by the members of the Monro family. Alexander Monro Primus (1697-1767) held it from 1726 until 1754; his son Alexander Monro Secundus (1733-1817) succeeded him in 1758; and Alexander Monro Tertius (1773-1859) held the chair from 1817 until 1846. While Tertius’ relevance lies on the fact that he continued the work of his father and grandfather, Primus and Secundus are one of the main reasons why the medical school at Edinburgh was considered the best of its time. Of course, the experimental method applied by the Monro’s was one of the reasons for their success.

Monro Primus studied at Leiden under Herman Boerhaave in 1718, and by in 1720 he was back at Edinburgh giving public lectures on anatomy. In 1726 he published hisAnatomy of the Humane Bones, which was widely read throughout the eighteenth century. The book was intended to be used by those students attending Monro’s lectures, where he demonstrated on corpses to illustrate the theory. In fact, the Professor’s insistence on the importance of performing dissections on corpses for his lectures was such that it was suspected that Monro and his students were grave robbing. In the preface to the second edition of his book Monro claims that all the facts included in his book, even those he has taken from other authors have been confirmed by experiments:

In executing these [parts I and II of his book], I have taken all the assistance I could from Books, but have never asserted any anatomical Fact on their Authority without consulting the Life, from which all the Descriptions are made; and therefore the Quotations from such Books, serve only to do Justice to the Authors… Besides anatomists, I have also named several other Authors [for example Boyle] to confirm my reasoning by practical Cases.

Monro Primus was a very active figure in the Edinburgh enlightenment. As the editor of the volumes of essays published by his Medical Society of Edinburgh, he calls for the emphasis on facts and observation of the experimental method to be applied in Medicine. He tells us that he ‘principal part of medicine is:

The Knowledge and Cure of Diseases, which chiefly depend on Observations of Facts that ought to be frequently repeated before any certain Axiom in Physick can be built on them.

Monro Primus’ work was continued by his son. Though Secundus continued using the text written by his father in his anatomy lectures, he published and contributed to the knowledge of the brain and the nervous system. All his texts contain detailed descriptions of the experiments he performed, besides the constant use of the rhetoric of the experimental philosophy and methodological statements confirming the use of experimental methods in medicine. A lot of his work stems from experiments performed on animals, notably a number of essays published in the collection of essays of the Royal Society of Edinburgh and his 1793 book Experiments on the nervous system, with opium and metalline substances, made chiefly with the view of determining the nature and effects of animal electricity. The way such book is structured is typical of experimental philosophy. Monro begins by giving some observations on the nervous system of frogs (which he used for his experiments); this is followed by a detailed description of the experiments and then he deduces “Corollaries from the above Facts and Experiments.”

In an earlier book, where he describes in some detail his main claim to fame (the discovery of the interventricular foramen of the brain), he calls for a stop to speculation and focus instead on facts and experiments. He refers to an experiment carried out by Dr. Albrecht von Haller which he describes and then tells us:

But instead of speculating farther, let us learn the effects of experiments and endeavour from these to draw plain conclusions.

The contrast between speculative and experimental approaches is also stated in his last major work, Three Treatises. On the Brain, the Eye and the Ear (1797):

An anatomist, reasoning a priore, would be apt to suppose, that the Water, in the Hydrocephalus Internus, should be as often found immediately within the Dura Matter, between it and the Outer-side of the Brain, Cerebellum, and Spinal Marrow, as within the Ventricles of the Brain. Experience, however, proves that it is generally collected within the ventricles; and, as I have not met with a single instance in which the Water was entirely on the Outer-side of the Brain, (although I am far from doubting the possibility of the fact), I cannot help suspecting that this happens much more rarely than it is supposed by Authors.

We can see then that the call for the application of the experimental method in medicine that started in the seventeenth century was characteristic of the medical school at Edinburgh in the eighteenth century. With the Monro dynasty in charge, the methodology promoted by Herman Boerhaave (Primus’ teacher) became the preferred for the training and practice of physicians in Scotland, with the Edinburgh medical school rising to its reputation of the best school in the world.

In my last post I claimed that the London physician Thomas Sydenham (1624–1689) faced much opposition during his professional career, and yet his posthumous reputation was that of the experimental physician par excellence. But was Sydenham the first experimental physician, the first English Hippocrates?

This question raises, in turn, the further issue of the extent to which the experimental philosophy, which emerged in England in the late 1650s and early 1660s, influenced English medicine. The hallmarks of Sydenham’s method – at least as championed by John Locke, the Dutch physician Herman Boerhaave and the Italian Giorgio Baglivi – were his commitment to natural histories of disease, his strident opposition to hypotheses and speculation, and his strong emphasis on observation. Interestingly, each of these methodological tenets can be found in the writings of physicians, and especially the chymical physicians (who opposed the Galenists of the College of Physicians), in England from the late 1650s.

Opposition to dogmatism and speculation was focused on the Galenists who, as the polemicist Marchamont Nedham claimed:

in a manner after their own Phantasie, framed the Art of Physick into a general Method, after the fashion of some Speculative Science; and so by this means, a copious form of Doctrin, specious enough, but fallacious and instable, was built’ (Medela medicinae, London, 1665, p. 238)

By contrast, there was a strong emphasis on observation and experiment amongst the chymical physicians. George Starkey, the American émigré, whose chymical medicine had a profound influence on Boyle, but who died of the plague in 1665, opens his Nature’s Explication (London, 1657, p. 1), which is dedicated to Boyle, with the following claim:

What profit is there of curious speculations, which doe not lead to real experiments? to what end serves Theorie, if not appplicable unto practice.

In 1665 in his Galeno-Pale, the chymical physician George Thomson entitled his tenth chapter ‘An Expostulation why the Dogmatists will not come to the touchstone of true Experience’. Thomson explicitly identifies himself as an experimental physician in his Misochymias elenchos … with an assertion of experimental philosophy, London, 1671.

Moreover, very early in the life of the Royal Society there were calls for natural histories of disease. Christopher Wren and Robert Boyle both set this as a desideratum for medicine and saw it as part of the broader program of Baconian natural history that the Society was pursuing. And in the 1660s Bacon’s method of natural history was affirmed and practised by physicians of the likes of Timothy Clarke and Daniel Coxe. Clarke had been involved in the exciting blood transfusion experiments of the mid-1660s and Coxe was a chymical physician, who even tried, though without much success, to get Sydenham interested in chymistry.

It is pretty clear then that Sydenham was not the first English physician to adopt and employ the new method of the experimental philosophers. Indeed, from the time that it first emerged, the experimental philosophy was applied in medicine. Why is it then, that Sydenham and not Clarke, Coxe or Thomson is hailed as the English Hippocrates? Part of the answer must lie in the fact that the chymical physicians were decimated by the plague in 1665, for they stayed in London in the belief that they could cure it. Part of the answer also lies in the politics of Restoration medicine and the mixed fortunes of the College of Physicians and its vexed relations with the Royal Society. And yet there must have been other factors involved. I have documented the emergence of Sydenham’s posthumous reputation in ‘The creation of the English Hippocrates’ which appears in Medical Historythis month. But I am not satisfied that I have a full understanding of the Sydenham phenomenon and I look forward to hearing insights that others might have.

The London physician Thomas Sydenham (1624–1689) is regarded today as one of the greatest physicians of the seventeenth century. He is even claimed to have had an influence on the philosophy of John Locke. But what exactly is the basis of Sydenham’s reputation?

A careful study of the appearance of Sydenham’s name in the medical writings of the latter decades of the seventeenth century and the correspondence of his friends and associates reveals that during his professional years he faced constant opposition and criticism. Henry Oldenburg, Secretary of the Royal Society, said of him in a letter to Robert Boyle (24 December 1667): ‘with so mean and un-moral a Spirit I can not well associate’. Sydenham was never to become a Fellow of the Royal Society or of the College of Physicians.

However, his posthumous reputation is markedly different. After his death, Sydenham was praised for three things: his commitment to natural histories of disease; his decrying of hypotheses and speculation; and his Hippocratic emphasis on observation. Interestingly, these are the hallmarks of the experimental philosophy. Witness, for example, what Locke says of him in a letter to Thomas Molyneux of 1 November 1692:

I hope the age has many who will follow his example, and by the way of accurate practical observation, as he has so happily begun, enlarge the history of diseases, and improve the art of physick, and not by speculative hypotheses fill the world with useless, tho’ pleasing visions.

By the early eighteenth century Sydenham’s name could hardly be mentioned without effusive praise, such as that found in George Sewell’s ode to Sir Richard Blackmore:

Too long have we deplor’d the Physick State, …
Then vain Hypothesis, the Charm of Youth,
Oppose’d her Idol Altars to the Truth: …
Sydenham, at length, a mighty Genius, came,
Who founded Medicine on a nobler Frame,
Who studied Nature thro’, and Nature’s Laws,
Nor blindly puzzled for the peccant Cause.
Father of Physick He—Immortal Name!
Who leaves the Grecian [Hippocrates] but a second Fame:
Sing forth, ye Muses, in sublimer Strains
A new Hippocrates in Britain reigns.

These comments are of the most general nature. There is nothing about the actual content of Sydenham’s medical theories or therapeutics, which were so harshly criticized while he was alive. It is all about his methodology and it is cashed out in terms of the experimental philosophy.

Thomas Sydenham, by a remarkable change in fortunes, came to be regarded as the archetypal experimental physician largely thanks to his posthumous promoters such as John Locke. Sydenham, for better or for worse, was the experimental physician that the promoters of the experimental philosophy had to have.

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